Module java.base
Package java.io

Class ObjectInputStream.GetField

java.lang.Object
java.io.ObjectInputStream.GetField
Enclosing class:
ObjectInputStream
public abstract static class ObjectInputStream.GetField extends Object
Provide access to the persistent fields read from the input stream.

  • Constructor Summary

    Constructors
    Constructor
    Description
    GetField()
    Constructor for subclasses to call.

  • Method Summary

    Modifier and Type
    Method
    Description
    abstract boolean
    defaulted(String name)
    Return true if the named field is defaulted and has no value in this stream.
    abstract boolean
    get(String name, boolean val)
    Get the value of the named boolean field from the persistent field.
    abstract byte
    get(String name, byte val)
    Get the value of the named byte field from the persistent field.
    abstract char
    get(String name, char val)
    Get the value of the named char field from the persistent field.
    abstract double
    get(String name, double val)
    Get the value of the named double field from the persistent field.
    abstract float
    get(String name, float val)
    Get the value of the named float field from the persistent field.
    abstract int
    get(String name, int val)
    Get the value of the named int field from the persistent field.
    abstract long
    get(String name, long val)
    Get the value of the named long field from the persistent field.
    abstract short
    get(String name, short val)
    Get the value of the named short field from the persistent field.
    abstract Object
    get(String name, Object val)
    Get the value of the named Object field from the persistent field.
    abstract ObjectStreamClass
    getObjectStreamClass()
    Get the ObjectStreamClass that describes the fields in the stream.

    Methods declared in class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • GetField

      public GetField()
      Constructor for subclasses to call.

  • Method Details

    • getObjectStreamClass

      public abstract ObjectStreamClass getObjectStreamClass()
      Get the ObjectStreamClass that describes the fields in the stream.
      Returns:
      the descriptor class that describes the serializable fields

    • defaulted

      public abstract boolean defaulted(String name) throws IOException
      Return true if the named field is defaulted and has no value in this stream.
      Parameters:
      name - the name of the field
      Returns:
      true, if and only if the named field is defaulted
      Throws:
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if name does not correspond to a serializable field

    • get

      public abstract boolean get(String name, boolean val) throws IOException
      Get the value of the named boolean field from the persistent field.
      Parameters:
      name - the name of the field
      val - the default value to use if name does not have a value
      Returns:
      the value of the named boolean field
      Throws:
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if type of name is not serializable or if the field type is incorrect

    • get

      public abstract byte get(String name, byte val) throws IOException
      Get the value of the named byte field from the persistent field.
      Parameters:
      name - the name of the field
      val - the default value to use if name does not have a value
      Returns:
      the value of the named byte field
      Throws:
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if type of name is not serializable or if the field type is incorrect

    • get

      public abstract char get(String name, char val) throws IOException
      Get the value of the named char field from the persistent field.
      Parameters:
      name - the name of the field
      val - the default value to use if name does not have a value
      Returns:
      the value of the named char field
      Throws:
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if type of name is not serializable or if the field type is incorrect

    • get

      public abstract short get(String name, short val) throws IOException
      Get the value of the named short field from the persistent field.
      Parameters:
      name - the name of the field
      val - the default value to use if name does not have a value
      Returns:
      the value of the named short field
      Throws:
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if type of name is not serializable or if the field type is incorrect

    • get

      public abstract int get(String name, int val) throws IOException
      Get the value of the named int field from the persistent field.
      Parameters:
      name - the name of the field
      val - the default value to use if name does not have a value
      Returns:
      the value of the named int field
      Throws:
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if type of name is not serializable or if the field type is incorrect

    • get

      public abstract long get(String name, long val) throws IOException
      Get the value of the named long field from the persistent field.
      Parameters:
      name - the name of the field
      val - the default value to use if name does not have a value
      Returns:
      the value of the named long field
      Throws:
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if type of name is not serializable or if the field type is incorrect

    • get

      public abstract float get(String name, float val) throws IOException
      Get the value of the named float field from the persistent field.
      Parameters:
      name - the name of the field
      val - the default value to use if name does not have a value
      Returns:
      the value of the named float field
      Throws:
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if type of name is not serializable or if the field type is incorrect

    • get

      public abstract double get(String name, double val) throws IOException
      Get the value of the named double field from the persistent field.
      Parameters:
      name - the name of the field
      val - the default value to use if name does not have a value
      Returns:
      the value of the named double field
      Throws:
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if type of name is not serializable or if the field type is incorrect

    • get

      public abstract Object get(String name, Object val) throws IOException, ClassNotFoundException
      Get the value of the named Object field from the persistent field.
      Parameters:
      name - the name of the field
      val - the default value to use if name does not have a value
      Returns:
      the value of the named Object field
      Throws:
      ClassNotFoundException - Class of a serialized object cannot be found.
      IOException - if there are I/O errors while reading from the underlying InputStream
      IllegalArgumentException - if type of name is not serializable or if the field type is incorrect